This invention relates to nylon polymer systems having improved flame retardant properties.
In recent years concern for the fire hazards presented by many polymeric materials has led to the development of a variety of flame retardant or fire retardant additive compositions designed for incorporation in such polymeric materials. Thus, for example, it is known to impart flame retardant properties to polymeric materials by incorporation therein of various halogen containing additives, particularly chlorinated organic compounds. Although such additives have been found to effectively enhance the flame retardant properties of polymeric systems, many have been found to present environmental problems, particularly with respect to the release of toxic gases during combustion. Furthermore, the presence of halogen in the polymers has been found to present problems with respect to corrosion of equipment during processing of the polymer. In addition, a number of the prior art flame retardant additives are relatively low thermal stability, and exhibit a tendancy to degrade during processing such as molding, at elevated temperatures.
It is an object of the present invention to provide improved flame retardant additive compositions for use in polymeric systems. It is a further object to provide flame retardant additive compositions having a relatively high thermal stability and resistance to degradation and decomposition under processing conditions at elevated temperatures. It is a still further object to provide flame retardant polymeric compositions exhibiting a substantially decreased tendency toward corrosion of processing equipment during processing. It is a still further object to provide such polymeric compositions characterized by the formation of char during combustion and the minimization of the release of toxic gases.